Exploring Encompass RNA PreE (At-Home) Test

Dr. Chapa critically examines the Mervy Encompass RNA PreE (At-Home) Test, a new direct-to-consumer blood test marketed to predict preterm preeclampsia between 18 and 22 weeks of pregnancy. While acknowledging the scientific legitimacy of using cell-free RNA signatures and AI algorithms to identify high-risk pregnancies—with a reported 90% positive predictive value—Dr. Chapa raises major concerns about clinical actionability. The test’s major limitation is timing: aspirin, the only proven preventive treatment, is most effective when started by 16 weeks, but the test is typically administered at 18–22 weeks, missing the optimal window. He emphasizes that even with a positive result, there is no targeted treatment beyond aspirin, and no evidence yet that this test improves maternal or neonatal outcomes. He also highlights the test’s narrow eligibility criteria—excluding patients with diabetes, hypertension, lupus, prior preeclampsia, or multiple gestations—making it relevant to only a small subset of pregnant patients. Dr. Chapa advocates for universal low-dose aspirin (81 mg) starting at 12 weeks, with higher doses for high-risk patients, and warns against the potential for patient anxiety and physician confusion due to direct-to-consumer marketing. He concludes that while innovation is welcome, the test lacks clinical utility until real-world data confirms its impact on outcomes. Key takeaways include: (1) The Mervy Encompass Test has strong predictive accuracy for preterm preeclampsia but is clinically limited by delayed timing; (2) Aspirin remains the only proven preventive treatment, and it should be started by 16 weeks; (3) Universal aspirin use (with dose escalation for high-risk patients) is a more effective and equitable strategy than risk-based testing; (4) Direct-to-consumer testing can create clinical confusion and should be approached with caution; (5) Real-world, multi-site studies are needed before this test can be recommended in clinical practice. The episode ends with a strong endorsement of aspirin as a foundational preventive tool and a call for evidence-based innovation.